Shock-absorber.



AWHLABLE COPY.

3. FLENTJE. SHOCK ABSORBER.

APPLICATION FILED OUT. 12, 1911.

Patented Nov. 26, 1912.

' to the requirements of use.

- ERNST FLENTJ'E, 0F CAMBRIDGE, MASSACHUSETTS.

SHOCK-ABSORBER.

Specification of Letters Patent.

Patented Nov. 26, 1912.

Application filed October 12, 1911. Serial No. 654,280. I

To all whom it may concern:

Be it known that I, ERNST FLENTJE, a citizen of the United States,residing at Cambridge, county of Middlesex, and State of Massachusetts,have invented an Improvement in Shock-Absorbers, of which the followingdescription, in connection with the accompanying drawing, is aspecification, like characters on the drawing representing like parts.

This invention relates to shock absorbers forautomobiles and similarvehicles and is in the nature of an improvement on the device shown inmy Patent No. 899,662, dated September 29, 1908. The device shown insaid patent comprises a cylinder connected to the axle of the automobileand adapted to contain liquid and a piston connected to the frame of theautomobile and operating in said cylinder, said piston having portstherein which are controlled by valves arranged so as to permit thepiston to move freely in the cylinder while the automobile spring isbeing compressed but to prevent the rapid recoil movement of the spring.

Some automobile springs require a greater resistance to properlycheckthe recoil thereof than other s rings do. Moreover, when anautomobile 1S heavily loaded a less resistance is required in the shockabsorberto give an easy riding movement than when the automobile carriescomparatively little load. In my present invention I have provided forvary-mg the resistance to the movement of the piston in the cylinderwhereby the shock absorber can be readily adjusted I have also otherwiseimproved shock absorbers, all as will be more full-yhereinafterdescribed and I then pointed out in the appended claim.

Referring to the drawings wherein I have shown one embodiment of myinvention, Figure l is a sectional view of my improved shock absorbertaken in a vertical plane parallel with the axis of the automobile; Fig.2 is a sectional view taken in a plane at right angles to that of Fig. 1with the shock absorber shown in section on the line M, Fig. 1; Fig. 3is a sectional view on the line wa2, Fig. 4-; Fig. 4 is a section on theline yy, Fig. 3; Fig. 5 is a fragmentary perspective view of the lowerend of the valve in the piston rod; Fig. 6 is a perspective view of thehanger connected to the axle; Fig. 7 shows a slightly different form ofhanger from that shown in Figs. 2 and 6.

In the drawings I have shown only sufiicient parts of an automobile toillustrate the manner in which the shock absorber is used because theoperation of shock absorbers of this nature is well known to thoseskilled in the art.

3 designates a portion of the side sill of an automobile body and 4indicates the axle.

5 designates the cylinder of the shock absorber which is adapted tocontain glycerin or some other suitable liquid and 6 1s a pistonoperating in the cylinder. The cylinder is connected to the axle 4 bymeans of a hanger spring seat of the axle beneath the spring 48, an arm49 which extends laterally from this head portion and overlies the axle4, and the portion 50 which extends laterally and downwardly from thearm 49 and terminates in a foot 51 carrying the staple 52 which isconnected to the eye 53 on the bottom of the cylinder. The arm 49 isshaped on its lower side to fit the upper face of the axle. Where theaxle is round, as shown in Fig. 2, the under side of the arm 49 will beformed with the curved seat 54 to fit the curvature of the axle, but ifthe axle is of the shape shown in Fig. 7 then the seat portion 54 willhave a corresponding shape and the arm will be preferably provided withthe lip 55 to engage the side of the axle. A clip 56 embraces the arm 49and the ends of the arms of the clip pass through a 'clamping member 57and are provided with 'the axle serves to prevent any lateral movementof the armand hanger. The piston 6 is provided with ports 10 that areada ted tobe closed by a valve 11 shown in the orm of an annular ring.This valve has secured thereto studs 12 which pass down throughapertures in the piston and are provided on their under sides with heads13 that engage the iston when the valve is open and serve to hmit theopening movement thereof.

When the automobile springs are compressed the piston descends and thevalve 11" opens automatically as far as the studs 12.

will permit, thus allowing the liquid to pass from the lower to theupper side of the piston. The bore of the piston rod 8 is open to thecylinder beneath the piston, and said piston rod is rovided wit theports 14 which communicate with the cylinder above the piston. When theautomobile spring recoils and the piston moves u wardly, the valve 11closes and liquid W111 be transferred from the upper to the lower sideof the piston through the ports 14, the size of which determines thespeed of movement of the piston. Situated within the piston is a valve15 in the form of a rod which is adaptedto control the size of the ports14 and the upper end 16 of which pro ects beyond the hanger 9 and isprovided with the squared end 17 for the reception of a wrenchv orsimilar tool. This valve is screw-threaded to .the interior of thepiston rod so that it can be screwed longitudinally of said piston rod.The lower end of the valve is provided with the slits 18, as clearlyseen in Figs. 3. and 5. B roperly adjusting the valve 15 the size 0; tiitrolled and these ports may be uncovered more or less depending upon therequirements of use. The slits 18 are for the purpose of preventing thevalve 15 from being adjusted so as to entirely close the ports 14. Theseslits are of such a length that when the valve15 is screwed down into-the piston rod as far as possible thereby carrying the lower end of thevalve below the ports 14, said slits will still communicate with theports and will furnish a small continuously-open passage through whichthe liq-- uid can pass. If, therefore, by accident or otherwise thevalve is screwed into the piston rod too far the device will still beoperative, for an open passage will be left for the transfer of llquid.

It sometimes happens that an automobile spring will have a violentrecoil during which the piston is drawn up 'to the top of the cylinder.To avoid the danger of the piston striking the top of the ,cylinderduring such violent recoil, I propose to so place the ports 14 that theywill be drawn into the stufiing box 20 before the piston reaches theupper limit of its movement, as shown in Fig. 2. It will thus be seenthat if there is a violentrecoil and the piston moves clear to e ports14 can be conthe upper end of the cylinder the fipgrts 14 will be closedby entering the stu g box before the piston strikes the cylinder head"and the liquid which is trapped in the upperend of the cylinder willprevent the con tact of the piston head .with the cylinder. I have alsoshown a shield or cover 34 which surrounds the piston rod and extendsfrom the stuffing box to the head 98 at the end of the piston rod andwhich serves to prevent any dust from being drawn into the stuffing boxb the movement of the piston. This shiel or cover is in the nature of aflexible tube which is connected at its upper end to-the head 98 bymeans of a wire 36 and at its lower end is connected to the stuflingbox. The stufling box is of that type in which the packing is acted uponby a spring and means are provided for adjusting the spring pressure aswear occurs. The packing is shown at 26 and it is acted upon by a spring27 the lower coil of which is beveled, as at 28, to engage the packing.

nected to the cap 30 and in order to provide for turning said ca withoutdisconnectin the shield 34 there rom I have made sai cap with thehexagonal portion 32 above which is a groove 40 adapted to receive abindin wire 41'that ties the lower end of the shield 34 to the cap. Withthis construction the hexagonal portion of the cap is always exposed sothat it can be tightened up whenever required and a swivel connection isprovided between the cap and the shield 34.

71 designates a spring surrounding the piston rod within the cover34'and which serves both to prevent the cover from engaging said rod andalso to cushion the downward movement of the piston.

I do not claim herein the manner of securing the leather covering 34 tothe cap nut 30, nor the particular type of hanger shown, but I reservethe right to claim these features in divisional applications.

} Having what I claim as new and desire to secure by Letters Patent isIn ashock absorber having a cylinder to contain liquid, a ported pistontherein, and a valve for closing said ports, the combination with ahollow piston rod. connected to the piston and open to the cylinderbelow the piston, said piston .rod havin ports communicating with thecylinder IfiJOVG the piston, of a valve within the piston rod forconfully described my invention,

troiling'said latter ports, said valve having In testimony whereof, Ihave signed m-y transverse slits therein and rovided .with a name tothis specification, in the presence of stem which projects beyon theiston rod two subscribing Witnesses.

and is screw-threaded thereto, sald slits be- ERNST FLENTJE. 5 ing of alength to be in communication with Witnesses:

the ports in the piston rod when the valve is LoUIs C. SMITH,

adjusted into its extreme lower position. THOMAS J. DRUMMOND.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, D. 0.

